Defining Width in Viewport Tag

Example of a Viewport tag:  <meta name=“viewport” content=“initial-scale=1”>

The above is the common viewport tag that should be added to the head section of every web page. 

Defining a Viewport tag fixed width: <meta name="viewport" content="width=500, initial-scale=1">

The above shows how to set a fixed width with the viewport tag for a mobile device.